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Human-object interaction detection can be mainly categorized into two core problems, namely human-object association detection and interaction understanding. Firstly, for association detection, previous methods tend to directly detect obvious human-object interaction pairs, while ignoring some interaction pairs that may have potential interaction relationships, which is contrary to the actual situation. Secondly, for the interaction understanding problem, traditional methods face the challenges of long-tailed distribution and zero-shot detection, which cannot flexibly deal with complex and changing real-world scenarios. To this end, adaptive Query Learning for HOI Detection via vision-language knowledge Transfer(QLDT) is proposed. Specifically, a two-stage dynamic matching scoring algorithm based on dynamically changing thresholds and scores is designed to explore obscure H-O pairs and labeling to enlarge the sample size. Secondly, a visual-language pre-trained model GLIP (Grounded Language-Image Pre-training), is introduced to enhance the model's interactive comprehension ability, extract the visual and linguistic features of the images through GLIP, minimize the gap with the predicted values using cross-entropy loss, and take the maximum value of the score with the obscure H-O pairs as the final prediction, which ensures the model's positivity. The proposed method shows excellent performance on both HICO-DET and V-COCO datasets, for HICO-DET, QLDT achieved 35.37% mAP on the full category, 30.15% mAP on the rare category, and also improved on all five zero-shot metrics. For V-COCO, 62.74% mAP and 67.71% mAP were achieved under Scenario 1 and 2, respectively. [ABSTRACT FROM AUTHOR]

Due to the enhanced-mode (E-mode) operation, AlGaN/GaN high-electron-mobility transistors (HEMTs) are considered to be safer for circuit operation. In order to improve the threshold voltage (Vth) of the device, this work provides a hybrid gate structure HEMT by embedding a P-GaN cap on the etched graded AlGaN barrier layer. Through simulation calculations, the P-GaN cap (thickness of P-GaN = 50 nm, concentration of P-type = 2 × 1018 cm−3) and the aluminum (Al) composition (Al:0.3 → 0.24), in the graded AlGaN barrier layer were optimized. Although simulation calculations show that the optimized P-GaN layer can significantly increase the device's Vth to 8.6 V and transconductance (gm) to 94.7 mS/mm, the device exhibits a lower saturation current (Isat). Therefore, to improve the output characteristics of the devices, the addition of an N-well in the GaN channel layer of such structures was proposed. It can increase the device's source–drain current while maintaining a steady Vth. Compared with the HEMT structure/combined P-GaN cap with recessed gate and a graded AlGaN barrier layer, the device with the added N-well exhibits a significant improvement of 11.2% in the saturation current (Isat = 718 mA/mm). The results demonstrate that HEMT structures combining recessed gates and P-GaN with N-well have promising applications in next-generation high-power devices. [ABSTRACT FROM AUTHOR]

Like GaN-based LEDs, the further improvement of InGaN based near UV LED performance also faces a typical problem: the spatial separation of carrier wave functions caused by the polarization electric field in the active region. In this paper, a novel three-layer asymmetric staggered quantum well with special gradually changing In-component distribution is proposed and applied to InGaN/AlGaN near UV LED to change the carrier distribution and improve the probability of carrier radiation recombination. The proposed new quantum well structure improves its energy band by controlling the In-component, to enhance the carrier limiting effect and then improve the possibility of carrier wave function overlap. Increased radiation recombination in the MQWs region will undoubtedly result from increased carrier wave function overlap, which will then enhance the luminescence performance of the structure. In conclusion, the simulation results show that compared with the traditional structure, the light output power (LOP) of the new structure is increased by 12.87% under the current condition of 100 A/cm2. [ABSTRACT FROM AUTHOR]

Artificial intelligence models play a crucial role in monitoring and maintaining railroad infrastructure by analyzing image data of foreign objects on power transmission lines. However, the availability of publicly accessible datasets for railroad foreign objects is limited, and the rarity of anomalies in railroad image data, combined with restricted data sharing, poses challenges for training effective foreign object detection models. In this paper, the aim is to present a new dataset of foreign objects on railroad transmission lines, and evaluating the overall performance of mainstream detection models in this context. Taking a unique approach and leveraging large-scale models such as ChatGPT (Chat Generative Pre-trained Transformer) and text-to-image generation models, we synthesize a series of foreign object data. The dataset includes 14,615 images with 40,541 annotated objects, covering four common foreign objects on railroad power transmission lines. Through empirical research on this dataset, we validate the performance of various baseline models in foreign object detection, providing valuable insights for the monitoring and maintenance of railroad facilities. [ABSTRACT FROM AUTHOR]

For quantum communications, single-photon detection, millimeter wave detection and other space projects, all of them need to work at liquid helium temperatures to achieve excellent performance. The closed-cycle helium Joule-Thomson cryocooler (JTC) is currently one of the mainstream solutions to realize the liquid helium temperature. While realizing the liquid helium temperature, the detector has strict requirements on the temperature fluctuation of the JTC, because the thermal noise caused by the JTC temperature fluctuation will have a critical impact on the detection performance. The typical closed-cycle helium JTC is precooling by a two-stage precooler. When the operating parameters of the JTC compressor remain unchanged, the change of the precooler is the main factor that affects the temperature fluctuation of the JTC. To explore the influence mechanism of JTC temperature fluctuations, experimental and theoretical studies are carried out. Based on the real gas equation of state, the influence of various parameters on the evaporator temperature fluctuations is explained. Research results show that the increase in temperature of each stage will cause the temperature of the JTC to increase. Especially, the change of the secondary precooling temperature (Tpre2) has the most obvious influence on JTC temperature. Furthermore, the influence of the JT compressor's buffer tank volume Vb on temperature fluctuation is studied. By increasing the Vb, the JTC temperature fluctuation caused by the temperature change of the precooler can be effectively reduced. [ABSTRACT FROM AUTHOR]

Objectives: There is increasing evidence of the effectiveness of self-compassion in promoting psychological well-being. However, there are limited validated tools to assess self-compassion among youths, especially in China. The purpose of this study was to examine the psychometric properties of the Chinese version of the Self-Compassion Scale for Youth (SCS-Y). Methods: A total of 1298 adolescents completed the SCS-Y and questionnaires on mental health outcomes such as psychological resilience, well-being, interpersonal competence, anxiety, and depression. Psychometric properties of the SCS-Y were investigated by structural, concurrent, and incremental validity analyses, as well as reliability analyses. Confirmatory factor analysis (CFA) and exploratory structural equation modeling (ESEM) were applied to examine the one-factor, two-factor, six-factor correlated, bifactor, and two-bifactor models. Results: The six-factor correlated CFA and ESEM, as well as the bifactor ESEM, showed good model fit indices. The six-factor correlated CFA solution demonstrated better item factor loadings whereas the interfactor correlations of six-factor correlated and bifactor ESEM were superior. The scores of the Chinese SCS-Y had significant positive correlations with psychological resilience, subjective well-being, and interpersonal competence but negative correlations with depressive and anxiety symptoms, indicating good concurrent validity. Incremental validity of the SCS-Y was also supported by the significant prediction of less depression and anxiety after adjusting for demographic and other psychological variables. The Chinese SCS-Y had satisfactory internal consistency. Conclusions: The findings suggest that the Chinese version of the SCS-Y has good psychometric properties and can be used as a reliable and valid instrument to assess self-compassion among Chinese youth. [ABSTRACT FROM AUTHOR]

Photosynthesis is a key process linking carbon and water cycles, and satellite-retrieved solar-induced chlorophyll fluorescence (SIF) can be a valuable proxy for photosynthesis. The TROPOspheric Monitoring Instrument (TROPOMI) on the Copernicus Sentinel-5P mission enables significant improvements in providing high spatial and temporal resolution SIF observations, but the short temporal coverage of the data records has limited its applications in long-term studies. This study uses machine learning to reconstruct TROPOMI SIF (RTSIF) over the 2001–2020 period in clear-sky conditions with high spatio-temporal resolutions (0.05° 8-day). Our machine learning model achieves high accuracies on the training and testing datasets (R2 = 0.907, regression slope = 1.001). The RTSIF dataset is validated against TROPOMI SIF and tower-based SIF, and compared with other satellite-derived SIF (GOME-2 SIF and OCO-2 SIF). Comparing RTSIF with Gross Primary Production (GPP) illustrates the potential of RTSIF for estimating gross carbon fluxes. We anticipate that this new dataset will be valuable in assessing long-term terrestrial photosynthesis and constraining the global carbon budget and associated water fluxes. Measurement(s) Solar-Induced Fluorescence Technology Type(s) machine learning algorithms [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting is limited by kinetics-sluggish oxygen evolution, in which the activity of catalysts depends on their electronic structure. However, the influence of electron spin polarization on catalytic activity is ambiguous. Herein, we successfully regulate the spin polarization of Co3O4 catalysts by tuning the concentration of cobalt defects from 0.8 to 14.5%. X-ray absorption spectroscopy spectra and density functional theory calculations confirm that the spin polarization of Co3O4 is positively correlated with the concentration of cobalt defects. Importantly, the enhanced spin polarization can increase hydroxyl group absorption to significantly decrease the Gibbs free energy change value of the OER rate-determining step and regulate the spin polarization of oxygen species through a spin electron-exchange process to easily produce triplet-state O2, which can obviously increase electrocatalytic OER activity. In specific, Co3O4-50 with 14.5% cobalt defects exhibits the highest spin polarization and shows the best normalized OER activity. This work provides an important strategy to increase the water splitting activity of electrocatalysts via the rational regulation of electron spin polarization. [ABSTRACT FROM AUTHOR]

Background and aims: Stroke is currently the leading cause of death in China; however, the past decade has produced no new epidemiological studies of stroke. Therefore, the current study aimed to compare the prevalence and risk factors of stroke between 2010 and 2019. Methods: A comparative study was used to analyze the prevalence of risk factors for stroke in a population aged 65 years or older between 2010 and 2019. Demographic characteristics, risk factors, medical history, and other clinical characteristics were collected for all participants via door-to-door interviews and inpatient hospital records. Results: The standardized prevalence of stroke was 7.9% in 2010 and 14.2% in 2019 (p < 0.001). The prevalence of stroke was significantly higher in men than in women (p < 0.05) for all age groups. The risk factors of stroke were being male, hypertension, and diabetes mellitus in both 2010 and 2019. When comparing the risk factors between 2010 and 2019, these risk factors were statistically significantly more strongly associated with stroke in 2019 than in 2010. Conclusion: The current study suggests that the prevalence of stroke increased nearly by twofold in a population aged 65 years or older within the past 10 years. Hypertension, diabetes mellitus, and being male were the primary risk factors. In addition, these factors were more significantly associated with stroke in 2019 compared to 2010. [ABSTRACT FROM AUTHOR]

The flow field structure on the bipolar plate significantly affects the performance of the proton exchange membrane electrolysis cell (PEMEC). This paper proposes a new interdigitated-jet hole flow field (JHFF) design to improve the uniformities of liquid saturation, temperature, and current density distributions. The common single-path serpentine flow field (SSFF) and inter-digitated flow field (IFF) are used as comparative references to constitute three PEMEC cases. An advanced numerical model has been established to simulate the performance of the PEMEC using CFD software. The results show that, due to the perpendicular mainstream and the pressure difference, the JHFF enhances the mass and heat transfer inside the porous electrode by introducing strong forced convection, which promotes gas removal underneath the ribs and cooling. Compared with the comparative flow fields, the uniformities of liquid saturation, temperature, and current density distributions by using the JHFF at the anode side are increased by 19.1%, 53.2%, and 40.4%, respectively. Further, mainly owing to the largest conductive area, the PEMEC with the JHFF has superior polarization performance, which is 8.05% higher than the PEMEC with the SSFF. [ABSTRACT FROM AUTHOR]

The raw syngas effluent from a fluidized bed gasifier typically contains a large amount of fly ash having a high concentration of carbon, which is undesirable. The present work examined the newly developed entrained-flow gasification technology intended to gasify raw syngas. Simulation of gas–solid flow and reaction behavior in an industrial-scale entrained-flow gasifier applying this new technology was first performed to obtain a better understanding of the particle flow and gasification characteristics. In addition, the devolatilization and heterogeneous reactions of fly ash particles were characterized by thermogravimetric analysis and user-defined function. The predictions from the simulation showed good agreement with the results of in situ experimental measurements. The combustion reaction for raw syngas occurred in the burner jet zone. As the hot gaseous products diffused, gasification reactions dominated the other zones. When burner inclination angle was 0°, 8.5°, and 25.5°, the temperature at the bottom outlet of the gasifier was lower than the ash flow temperature with the value of 1360 °C. Solid slag formed and blocked the outlet. By comparison, this gasifier with the burner inclination angle of 17° could discharge the liquid slag and function as a continuous operation. In this way, the carbon conversion in fly ash reached the maximum value of 87%. [ABSTRACT FROM AUTHOR]

Vibrationally excited molecular hydrogen has been commonly observed in the dense photo-dominated regions (PDRs). It plays an important role in understanding the chemical evolution in the interstellar medium. Until recently, it was widely accepted that vibrational excitation of interstellar H2 was achieved by shock wave or far-ultraviolet fluorescence pumping. Here we show a further pathway to produce vibrationally excited H2 via the water photochemistry. The results indicate that the H2 fragments identified in the O(1S) + H2(X1Σg+) channel following vacuum ultraviolet (VUV) photodissociation of H2O in the wavelength range of λ = ~100-112 nm are vibrationally excited. In particular, more than 90% of H2(X) fragments populate in a vibrational state v = 3 at λ~112.81 nm. The abundance of water and VUV photons in the interstellar space suggests that the contributions of these vibrationally excited H2 from the water photochemistry could be significant and should be recognized in appropriate interstellar chemistry models. Understanding the source of vibrationally excited molecular hydrogen is an essential prerequisite for understanding the chemical evolution in the universe. Here the authors report a photodissociation pathway to produce vibrationally excited H2 via the water photochemistry. [ABSTRACT FROM AUTHOR]

Background: Heart failure (HF) is a global public health problem of increasing importance. The association between acute exposure to air pollution and HF has been well established in developed countries, but little evidence is available in developing countries where air pollution levels are much higher. Objectives: To explore the associations between PM2.5 and HF hospitalizations in Yancheng, China. Methods: In this time-series study, daily HF hospitalizations admitted in three major hospitals in Yancheng from May 1, 2015 to Apr 30, 2020 were collected. We used a generalized additive model with quasi-Poisson regression to investigate the association between PM2.5 and HF hospitalizations. The robustness of the associations was tested using two-pollutant models, and we examined the potential effect modification by age, gender, and season via stratification analyses. Lastly, we pooled the concentration-response curves. Results: A total of 10,466 HF hospitalizations were recorded, with a daily average of 6 cases. We observed the most robust estimates on lag 0 day, and the associated increment in HF was 1.28% (95% CI 0.45%, 2.11%) for a 10-μg/m3 increase of PM2.5. The association remained after adjustment of O3, but not for NO2, CO, and SO2. The PM2.5-HF associations were positive in females, patients aged ≥ 65 years, and in cold season. The C-R relationship curve was generally increasing below 30 μg/m3. Conclusion: This study provided evidence on the association of PM2.5 with acute exacerbation of chronic heart failure, which may benefit future prevention strategy and policymaking. [ABSTRACT FROM AUTHOR]

The provenance of oxygen on the Earth and other planets in the Solar System is a fundamental issue. It has been widely accepted that the only prebiotic pathway to produce oxygen in the Earth's primitive atmosphere was via vacuum ultraviolet (VUV) photodissociation of CO2 and subsequent two O atom recombination. Here, we provide experimental evidence of three-body dissociation (TBD) of H2O to produce O atoms in both 1D and 3P states upon VUV excitation using a tunable VUV free electron laser. Experimental results show that the TBD is the dominant pathway in the VUV H2O photochemistry at wavelengths between 90 and 107.4 nm. The relative abundance of water in the interstellar space with its exposure to the intense VUV radiation suggests that the TBD of H2O and subsequent O atom recombination should be an important prebiotic O2-production, which may need to be incorporated into interstellar photochemical models. Three-body dissociation of water, producing one oxygen and two hydrogen atoms, has been difficult to investigate due to the lack of intense vacuum ultraviolet sources. Here, using a tunable free-electron laser, the authors obtain quantum yields for this channel showing that it is a possible route to prebiotic oxygen formation in interstellar environments. [ABSTRACT FROM AUTHOR]

Industrial-scale experiments were conducted to study the effects of tertiary air declination angle (TDA) on the coal combustion and steam temperature characteristics in the first 350-MW supercritical down-fired boiler in China with the multiple-injection and multiple-staging combustion (MIMSC) technology at medium and high loads. The experimental results indicated that as the TDA increased from 0° to 15°, the overall gas temperature in the lower furnace rose and the symmetry of temperature field was enhanced. The ignition distance of the fuel-rich coal/air flow decreased. In near-burner region, the concentration of O2 decreased while the concentrations of CO and NO increased. The concentration of NO decreased in near-tertiary-air region. The carbon in fly ash decreased significantly from 8.40% to 6.45% at a load of 260 MW. At a TDA of 15°, the ignition distances were the shortest (2.07 m and 1.73 m) at a load of 210 MW and 260 MW, respectively. The main and reheat steam temperatures were the highest (557.2°C and 559.4°C at a load of 210 MW, 558.4°C and 560.3°C at a load of 260 MW). The carbon in fly ash was the lowest (4.83%) at a load of 210 MW. On changing the TDA from 15° to 25°, the flame kernel was found to move downward and the main and reheat steam temperatures dropped obviously. The change of TDA has little effect on NOx emissions(660–681 mg/m3 at 6% O2). In comprehensive consideration of the pulverized coal combustion characteristics and the unit economic performance, an optimal TDA of 15° is recommended. [ABSTRACT FROM AUTHOR]

In a gas/particle two-phase test facility, a three-component particle-dynamics anemometer was used to measure the characteristics of gas/particle two-phase flows in a 29 megawatt (MW) pulverized coal industrial boiler equipped with a new type of swirling pulverized coal burner. The distributions of three-dimensional gas/particle velocity, particle volume flux, and particle size distribution were measured under different working conditions. The mean axial velocity and the particle volume flux in the central region of the burner outlet were found to be negative. This indicated that a central recirculation zone was formed in the center of the burner. In the central recirculation zone, the absolute value of the mean axial velocity and the particle volume flux increased when the external secondary air volume increased. The size of the central reflux zone remained stable when the air volume ratio changed. Along the direction of the jet, the peak value formed by the tertiary air gradually moved toward the center of the burner. This tertiary air was mixed with the peak value formed by the air in the adiabatic combustion chamber after the cross-section of x/d = 0.7. Large particles were concentrated near the wall area, and the particle size in the recirculation zone was small. [ABSTRACT FROM AUTHOR]

On the basis of 45,092 participants (mean age of 54.04 ± 13.09 years) from the Kailuan study, this study was performed to explore the relationships among total cholesterol (TC), brachial-ankle pulse wave velocity (BaPWV), and systolic blood pressure (SBP) and quantify their separate effects. The correlations among TC, SBP, and BaPWV were analyzed using multivariate linear regression models. Mediation analysis was performed to determine whether the effect of TC on SBP can be explained by arterial stiffness. Multivariate linear regression analysis showed that for every one standard deviation increase in TC and BaPWV, SBP increased by 0.33 mmHg and 0.044 mmHg, respectively; for every one standard deviation increase in TC, BaPWV increased by 5.34 cm/s. Mediation analysis showed that the TC-induced SBP elevation was mediated by arterial stiffness in more than half of the whole cohort (indirect effect, 0.73; percent mediated, 54.5%). Furthermore, the TC-induced SBP elevation was mediated by arterial stiffness in less than half of the males (indirect effect, 0.70; percent mediated, 47.9%); however, the results were not statistically significant in females. In conclusion, TC and BaPWV are positively correlated with SBP, whereas TC is positively correlated with BaPWV. Almost half of the increase in SBP contributed to TC is mediated by arterial stiffness. [ABSTRACT FROM AUTHOR]

Highlights: Introducing mechanisms of antitumor activation produced by bacteria-mediated bio-therapy in detail. Comprehensively reviewing multiple administration routes of bacterial bio-therapy in combination with different traditional anticancer therapeutic modalities over the recent 5 years. Discussing the potential benefits and challenges of this anticancer approach, and conveying the development tendency and the application prospect of this field.The use of bacteria to specifically migrate to cancerous tissue and elicit an antitumor immune response provides a promising platform against cancer with significantly high potency. With dozens of clinical trials underway, some researchers hold the following views: “humans are nearing the first commercial live bacteria therapeutic.” However, the facultative anaerobe Salmonella typhimurium VNP20009, which is particularly safe and shows anticancer effects in preclinical studies, had failed in a phase I clinical trial due to low tumor regression and undesired dose-dependent side effects. This is almost certain to disappoint people’s inflated expectations, but it is noted that recent state-of-the-art research has turned attention to bacteria-mediated synergistic cancer therapy (BMSCT). In this review, the foundation of bacteria-mediated bio-therapy is outlined. Then, we summarize the potential benefits and challenges of bacterial bio-therapy in combination with different traditional anticancer therapeutic modalities (chemotherapy, photothermal therapy, reactive oxygen and nitrogen species therapy, immunotherapy, or prodrug-activating therapy) in the past 5 years. Next, we discuss multiple administration routes of BMSCT, highlighting potentiated antitumor responses and avoidance of potential side effects. Finally, we envision the opportunities and challenges for BMSCT development, with the purpose of inspiring medicinal scientists to widely utilize the microbiome approach in patient populations. [ABSTRACT FROM AUTHOR]

Thermal contact resistance of solid–solid interface is involved in many fields such as aerospace, low-temperature superconductivity and electronic machinery. With the booming of aerospace technology, the requirements for space detectors continue to increase; the research on accurate prediction, measurement and utilization of thermal contact resistance is becoming increasingly serious. This article systematically summarizes and analyzes the research progress of thermal contact resistance. It also comparatively analyzes theoretical prediction models, steady-state and transient-state experimental methods and numerical analysis methods from different angles, and summarizes the advantages and disadvantages of different methods. Moreover, the effects of the influencing factors such as the physical properties, the surface state, the contact pressure, the contact temperature, the heat flux direction and the thermal interface materials on the solid–solid thermal contact resistance are also briefly described. Through this systematic comparative analysis, further development directions are pointed out. [ABSTRACT FROM AUTHOR]

Numerical simulations were conducted to study the effects of the pulverized-coal bias distribution in the primary air on the coal combustion and NOx generation characteristics of a 600-MW down-fired boiler with multiple-injection and multiple-staging combustion technology. The total pulverized-coal in the primary air was kept constant, and the ratio of the pulverized-coal mass flux in the fuel-rich coal/air flow to the total pulverized-coal mass flux (RPR) was set as 60%, 70%, 80%, and 90%. By changing the RPR, the excess air coefficient of the fuel-rich flow was adjusted from 0.700 to 0.467. It was found that numerical simulation results were almost in agreement with cold modeling and in situ experimental results respectively, including the flow fields in the lower furnace at the RPR of 80% and the heating processes for the fuel-rich coal/air flow at the RPR of 90%, which verified the rationality of the numerical model and the grid. The simulation results indicated that the change of RPR has little effect on the symmetry of the flow field in the furnace. With the increase of the RPR from 60 to 90%: (1) the maximum airflow declination angle near the tertiary air slot decreased from 71 to 66°, which indicates that the downward airflow penetration depth gradually decreased; (2) the ignition distance of the fuel-rich coal/air flow decreased from 1.2 to 0.9 m, and the high-temperature area in the furnace hopper decreased and the position gradually moved away from the hopper water walls; (3) the oxygen consumption rate at the initial combustion stage constantly accelerated, and the fuel NOx generation rate under the fuel-rich flow nozzle increased first and then decreased; (4) the NOx emissions at the furnace exit dropped from 778 to 662 mg/m3 at 6% O2, and the carbon in the fly ash decreased from 5.87 to 5.52%. Increasing the RPR reasonably controlled the excess air coefficient of the fuel-rich flow, and realized the high-efficiency combustion in the furnace and the reduction of NOx emissions simultaneously. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide radicals in the ground state, SH(X), and hydrogen disulfide molecules, H2S, are both detected in the interstellar medium, but the returned SH(X)/H2S abundance ratios imply a depletion of the former relative to that predicted by current models (which assume that photon absorption by H2S at energies below the ionization limit results in H + SH photoproducts). Here we report that translational spectroscopy measurements of the H atoms and S(1D) atoms formed by photolysis of jet-cooled H2S molecules at many wavelengths in the range 122 ≤ λ ≤155 nm offer a rationale for this apparent depletion; the quantum yield for forming SH(X) products, Γ, decreases from unity (at the longest excitation wavelengths) to zero at short wavelengths. Convoluting the wavelength dependences of Γ, the H2S parent absorption and the interstellar radiation field implies that only ~26% of photoexcitation events result in SH(X) products. The findings suggest a need to revise the relevant astrochemical models. Sulfur is abundant in the Universe, but the observed abundance ratio of SH to H2S doesn't agree with astrochemical models. The authors measure product state-resolved translational energy spectra of photoproducts in a jet-cooled H2S beam as a function of wavelength, showing that SH yield is lower than assumed in the models. [ABSTRACT FROM AUTHOR]

The bovine hydroxyapatite (BHA) was applied to prepare biological tissue engineering scaffolds by the method of extrusion freeforming. To achieve this goal, BHA were added to sodium alginate (SA) solution to form a slurry system in appropriate proportion. The resulting mixtures were fabricated to be a kind of controllable and porous scaffolds followed with cross-linking in 5% calcium chloride (CaCl2) solution for 24 h. After that, the scaffolds were sintered in air at 1 000, 1 100, 1 200 and 1 300 °C for 5 h. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) studies were performed on the scaffolds to analyze its microstructure and constituent. To explore the effect of sintering temperature on scaffolds, the compressive strength, volume shrinkage and water absorptivity of BHA-SA composite scaffolds after sintering were investigated. The research tests indicated the feasibility of applying BHA powder to 3D printing. Besides, the scaffolds sintered in a respectively lower temperature possess much more pores and performed higher water absorptivity, which means better cellular affinity. And scaffolds sintered between 1 100 and 1 200 °C presents higher compressive strength. [ABSTRACT FROM AUTHOR]

Recently, additive manufacturing is one of the most focused research topics due to its explosive development, especially in manufacturing engineering and medical science. In order to build 3D complex scaffolds with multi-biomaterials for clinical application, a new 3D multi-nozzle system with dual-mode drives, i.e. ejection and extrusion was developed. In this paper, much effort was made to gain fine control of droplet and excellent coordination during fabrication. Specifically, the parameters that influence the size and stability of droplet most was intensively studied. Considering that the biomaterials used in the future may have much difference in properties, the combination of parameters was investigated to facilitate the settings for certain-sized droplets, which are potentially eligible for bio-printing. The dispensing nozzles can work well both in independent and convergent mode, which can be freely switched. Outstanding to the most currently used 3D bio-printing techniques, this system can fabricate scaffolds with multimaterials of both low viscosity (by pneumatic dispensing) and high viscosity (through motor extrusion). It is highly expected that this system can satisfy clinical application in the near future. [ABSTRACT FROM AUTHOR]

The authors describe a nanocomposite that was obtained by in-situ deposition of CdS nanocrystals on mesoporous silica nanospheres (MSNs), and its use in an electrochemical immunoassay of human immunoglobulin G (HIgG). The MCN/CdS nanocomposite was covalently modified with the antibodies against HIgG and then employed in a voltammetric immunoassay at antibody-functionalized magnetic beads. Through sandwich immunoreaction, the MCN/CdS nanoprobes are quantitatively captured onto the magnetic beads where numerous Cd(II) ions are released in an acidic solution. The Cd(II) can be detected by anodic stripping voltammetry at a typical working potential of −0.78 V (vs. Ag/AgCl). In combination with the high loading of CdS on MSNs, the use of the stripping voltammetric analysis renders the method high sensitivity. A wide linear range varying from 0.01 to 100 ng mL−1 is obtained for HIgG detection with a lower detection limit at 2.9 pg mL−1. In addition, the preparation of the nanoprobe is inexpensive. The magnetic bead-based assay does not require complex manipulations. Therefore, this method is deemed to possess a wide scope in that it may be applied to other immunoassays.Schematic presentation of the preparation of the mesoporous silica nanosphere (MSN)/CdS nanocomposite for the electrochemical immunoassay of human IgG at magnetic beads. The high decoration of CdS on MSN and the stripping voltammetric analysis of Cd(II) ions render the method high sensitivity. [ABSTRACT FROM AUTHOR]

T-acute lymphoblastic leukemia (T-ALL) is an aggressive hematologic malignancy with complicated heterogeneity. Although expression profiling reveals common elevated genes in distinct T-ALL subtypes, little is known about their functional role(s) and regulatory mechanism(s). We here show that SHQ1, an H/ACA snoRNP assembly factor involved in snRNA pseudouridylation, is highly expressed in T-ALL. Mechanistically, oncogenic NOTCH1 directly binds to the SHQ1 promoter and activates its transcription. SHQ1 depletion induces T-ALL cell death in vitro and prolongs animal survival in murine T-ALL models. RNA-Seq reveals that SHQ1 depletion impairs widespread RNA splicing, and MYC is one of the most prominently downregulated genes due to inefficient splicing. MYC overexpression significantly rescues T-ALL cell death resulted from SHQ1 inactivation. We herein report a mechanism of NOTCH1-SHQ1-MYC axis in T-cell leukemogenesis. These findings not only shed light on the role of SHQ1 in RNA splicing and tumorigenesis, but also provide additional insight into MYC regulation. T-acute lymphoblastic leukemia is an aggressive cancer. Here the authors provide insights into the functional role of SHQ1, an H/ACA snoRNP assembly factor involved in snRNA pseudouridylation, in T-lymphoblastic leukemia cell survival through regulating the maturation of MYC mRNA. [ABSTRACT FROM AUTHOR]

Vascularization is crucial for bone regeneration after the transplantation of tissue-engineered bone grafts in the clinical setting. Growing evidence suggests that mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) are potently pro-angiogenic both in vitro and in vivo. In the current study, we fabricated a novel EV-functionalized scaffold with enhanced pro-angiogenic and pro-bone regeneration activities by coating decalcified bone matrix (DBM) with MSC-derived EVs. EVs were harvested from rat bone marrow-derived MSCs and the pro-angiogenic potential of EVs was investigated in vitro. DBM scaffolds were then coated with EVs, and the modification was verified by scanning electron microscopy and confocal microscopy. Next, the pro-angiogenic and pro-bone regeneration activities of EV-modified scaffolds were evaluated in a subcutaneous bone formation model in nude mice. Micro-computed tomography scanning analysis showed that EV-modified scaffolds with seeded cells enhanced bone formation. Enhanced bone formation was confirmed by histological analysis. Immunohistochemical staining for CD31 proved that EV-modified scaffolds promoted vascularization in the grafts, thereby enhancing bone regeneration. This novel scaffold modification method provides a promising way to promote vascularization, which is essential for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Micro-expressions (MEs) are momentary and subtle facial expression changes that typically have a short duration to reveal people's genuine emotions and thought processes. With the continuous advancement of deep learning techniques, more opportunities and challenges have been presented for research in the field of micro-expression recognition (MER). Due to the limitations and low intensity of ME movements, as well as the presence of subtle motions and limited sample data, a single-stream model structure that extracts features from a single view is unable to capture sufficient information. Therefore, this paper proposes the Triple-branch attention fusion network (Triple-ATFME) for MER. The proposed Triple-ATFME mainly consists of a preprocessing stage, a Triple-branch ShuffleNet module, and an adaptive channel attention module allowing the model to extract multi-view features through a multi-path network. Firstly, the MER framework extracts optical flow features from the cropped initial frame and peak frame of the facial region using the optical flow method. Multiple types of optical flow features are obtained. Secondly, the extracted features are put into the Triple-ATFME network to extract deep-level hidden features. The three sub-modules extract multi-view features. In order to alleviate the issue of the tendency that the model excessively focuses on local information during the feature fusion process, a simple effective adaptive channel fusion attention module (CFAM) is employed to calibrate the channel features and to facilitate the fusion of multi-view features. Finally, ablation experiments are conducted to demonstrate that the multi-view features and the Triple-ATFME network are more effective in learning MEs. Experimental results show that the proposed Triple-ATFME achieves UF1 and UAR of 0.7609 and 0.7565 on the combined dataset MEGC2019, demonstrating superior performance compared to state-of-the-art MER methods as evaluated in leave-one-out validation. [ABSTRACT FROM AUTHOR]